Patent GB-1472511-A (GB)
Title: Manufacture of construction panels
IPC: E04C2/36
Filed: 1975-01-22
Abstract: 1472511 Laminates J C FALKENBERG 22 Jan 1975 2851/75 Heading B5N A method of manufacturing a construction panel formed of two boards 2, 3 of nailable material, e.g. plywood, particle board, or fibre board held together in parallel relationship by elongate sheet metal, e.g. galvanized steel strips 4, 4<SP>1</SP>, 5, each strip having along each longitudinal edge a plurality of teeth which are embedded in the adjacent board, comprises providing strips which are deformed to a wave-like configuration (Fig. 4) and in an untensioned state are shorter than their final length in the finished product, gripping the ends of each strip with respective clamping units which are displaceable relative to each other, longitudinally stretching the strips to their final lengths so that their wavelength is increased and their amplitude decreased by moving the clamping units away from each other, aligning the boards on opposite sides of the stretched strips and pressing the boards together so that the teeth are embedded in the boards. Strips preferably extend both longitudinally and transversely of the panel and may be folded and clamped together at their ends during the method. Insulating material, e.g. mineral wool mats may be placed within the area defined by the strips during the method. A machine for carrying out the method comprises clamping units mounted on a supporting structure to be displaceable relative to each other for gripping the end portions of the strips and longitudinally streching the strips to their final lengths, locating means for aligning the boards on opposite sides of the stretched strips and means for pressing the boards together. In the embodiment shown in Figs. 8 and 9, a jig 30 has a frame supporting a bottom plate 33 liftable relative to the frame, beams 31 of the frame supporting a toothed rack 36 and a guide rail 37. A pair of transoms 40, one of which is fixed near one end of the frame, the other being movable along the frame support clamping units 70, 70<SP>1</SP>, stretching of the longitudinal strips 4, 4<SP>1</SP> being effected by moving the transom along the frame, stretching of the transverse strip 5 being effected by movement of the clamping units along the transom. Longitudinal rails 120, 120<SP>1</SP> movable to and from each other are provided to support holding means 140 carrying aligning rules 160 to support the longitudinal strips 4, 4<SP>1</SP> upright and correctly spaced from the longitudinal edges of the boards. A clamping unit is shown in Figs. 13 to 16 and consists of a box 71 open at the top and bottom and having holes in the side wall 72 for movement along the transom. A plate 74 is supported on the front wall 73 via T-grooves and rails 77, a second plate 75 is secured to the front wall 73, jaws 76, 76<SP>1</SP> being secured to the plates 74, 75, the position of jaw 76 relative to plate 74 being adjustable, plate 74 with jaw 76 being displaceable to and from fixed jaw 76<SP>1</SP> by shaft 81. Punching elements 85 are mounted in jaw 76 and corresponding recesses or grooves 86 are formed in jaw 76<SP>1</SP>. Spring located vertical pins 101, 101<SP>1</SP> are carried in tube 100 fixed to wall 73 to engage, together with corresponding pins on the other transom the vertical edges of the top and bottom boards for vertical alignment of the boards, lateral location of the boards being effected using plate 115 journalled on shaft 116 in plate 75 which carries a vertical tube containing spring loaded upper 111 and lower abutting pins. The jig frame may rest on a wheel and roller track leading to a press of shorter length than the panel.